Taming a toxic stew

Taming a toxic stew

Research being conducted by UM scientists could lead to a better understanding of harmful algal blooms fouling Florida’s waterways and coastline.

Research being conducted by UM scientists could lead to a better understanding of harmful algal blooms fouling Florida’s waterways and coastline.

by ROBERT C. JONES JR.
UM News 09-26-2018

CORAL GABLES, Fla. (September 26, 2018) – A PVC pipe fashioned into a pole and a few demijohns packed neatly away in the back of his van, Larry Brand sets out from his South Miami home just before dawn and races north along U.S. Route 27, headed for one of the hotspots of this year’s massive toxic algae bloom outbreak.

In a little over two and a half hours, he arrives at his destination—the Caloosahatchee River, just outside the city of Fort Myers—and with one of the sample bottles fastened to his makeshift pole, draws a one-liter sample of water from the tributary.

Brand would repeat this process at a handful of other bodies of water that day, capping the bottles and loading them back into his van for the drive back to Miami. It would be dark by the time he got home. “It’s usually a full day’s work, depending on where I go,” said the phytoplankton ecologist at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science.

From Lake Okeechobee to the St. Lucie Canal to the southern Everglades to Florida Bay, Brand collects samples from Florida waterways on a regular basis, taking them back to his Rosenstiel School lab to culture and measure levels of harmful algae.

One-Two Punch

This year, his work is doubly important. Not only is the toxic algae Karenia brevisstill causing the worst red tide along Florida’s southwest coast in more than a decade, darkening Gulf of Mexico waters, killing marine life and triggering respiratory distress and other ailments in locals and tourists, but also a freshwater blue-green algae called cyanobacteria has coated the Caloosahatchee and St. Lucie rivers and other freshwater canals.

What that means for the long-term health of residents remains unclear. But Brand, a professor of marine biology and ecology, is part of a UM team of scientists trying to find out.

“In one sense, algae are the good guys. If you didn’t have any algae at all in the ocean, you wouldn’t have any other life because it’s the basis of the food chain. But sometimes the algae get out of control. We know that red tide toxins get into the air and into seafood. The effects are immediate, and that’s what most of the research has concentrated on,” said Brand, noting that Karenia breviscan cause gastrointestinal and neurological disorders that develop within minutes, hours or days after exposure. “But now, we’re looking at these toxins in blue-green algae that can have long-term effects. And the big question is, could they be getting into the air?”

That’s where Cassandra Gaston and Kimberly Popendorf step in. With assistance from their students, Michael Sheridan and Kaycie Lanpher, the two Rosenstiel School researchers have been testing air samples collected near the same rivers, lakes, and streams where Brand has been gathering water samples. “We’re trying to find out whether or not some of the different harmful algal blooms that we get in Florida other than red tide can become aerosolized, specifically cyanobacteria, which there’s not a lot of data on,” said Gaston, an assistant professor of atmospheric sciences.

So the two researchers subject the air samples to a chemical extraction process, testing for the presence of any toxins. And in another experiment, they plan to place blue-green algae water samples provided by Brand into the smaller of two wind-wave tanks at the Alfred C. Glassell Jr., SUSTAIN laboratory, subject the samples to different wind speeds, and measure the concentration of toxins in any water-to-air transfer that occurs.

“We’d like to put all of our data together to come up with some means of having a degree of predictability,” said Popendorf, an assistant professor of ocean sciences.

It will be the first such usage of the tank, according to Brian Haus, professor of ocean sciences and director of the SUSTAIN lab.

Larry Brand holds a beaker containing a water sample of cyanobacteria (blue-green algae) collected from Lake Okeechobee, one of many freshwater bodies of water from which he regularly gathers specimens.

Larry Brand examines a map of Lake Okeechobee.

Health Effects

The tank that will run Gaston and Popendorf’s experiment will also serve as the test bed for Miller School of Medicine researcher Grace Zhai’s study on the health effects of being exposed to harmful algal blooms. An associate professor of molecular and cellular pharmacology, Zhai will expose fruit flies in the tank to aerosolized blue-green algae, recording whatever ill health effects the flies develop.

“It’s a difficult problem to study,” said Zhai, who works with fruit flies as models for neurological diseases and was once part of a team that found an algal toxin in the Western Pacific was responsible for a high incidence of a severe neurodegenerative disorder in males on the island of Guam.

“Toxic algae is in our environment and it’s getting concentrated. Not only can you inhale it but it’s also accumulating in the food chain,” Zhai explained. “No one has come close to showing toxicity from aerosolized particles, and no other animal model allows us to study this aspect of it, except fruit flies. So this is what we believe to be first-of-its-kind research.”

Brand, Gaston, Haus, Popendorf, Zhai, and others are part of a team of biomedical researchers, ocean and atmospheric scientists, and engineers that has received Phase II funding via the University’s U-LINK initiative for their project Integrating Oceans and Human Health Sciences.

“Most research has focused on human exposure to algal toxins in the water or seafood. With the exception of brevetoxin (produced by the Florida red tide), little is known about the health effects of breathing aerosols with other algal toxins in them,” team members have reported. “Our findings will be used to help devise strategies to lower risks.”

Another member of that team, Alberto J. Caban-Martinez, an assistant professor in the Miller School’s Department of Public Health Sciences, hopes to use silicon-based wristbands to measure anglers’ exposure levels to harmful algal blooms. The wristbands have already been used on Florida firefighters to test their exposure levels to poly aromatic hydrocarbons, which are produced when coal, oil, gas, wood, and garbage are burned. “But we’re in the very early stages of determining how the bands can be used to measure exposure to harmful algal blooms,” said Katerina Santiago, a research associate in Caban-Martinez’s lab.

Brand, who has spoken at county commission, city council, environmental, and citizens meetings in Southwest Florida, said it is the health effects of harmful algal blooms that most people are concerned about.

“A lot of residents live near canals,” said Brand, “and a lot of the blue-green algae gets blown by the wind into these dead-end waterways.”

He hopes the results the UM team of scientists produces will make a difference.

“One would hope that policymakers would take these facts into account and come up with some way of reducing the nutrient sources that are leading to these algal blooms,” said Brand, who in August spoke at a community meeting in Fort Myers where 200 people had to be turned away because the meeting site was already filled to capacity with 450 attendees. “People are very angry. It’s affecting their lives.”

Red Tide’s deadly toll

For nearly a year, the Southwest Florida coastline has been transformed into a marine graveyard with tons of fish, turtles, manatees, and dolphins all perishing from the toxic bloom.